one thing you should know about me is that I will ride Midnight and Aizawa's dick for the rest of time. That is my spouse and platonic wife right there and I will forever defend them.
Which means I will unprofessionally talk about Midnight and why I think so many redesigns fail (IN MY OPINION) and how much I hate people fucking up her character.
The whole point of Midnight's character is to be sexual; she is based off of being a BDSM dominatrix through costume and personality. She uses her good looks and sexual behavior in battle and in general in her work because she can use it well and because she wants to. She's not like some of the 1-A girls who didn't want to be exposed as much, such as Ochako and Momo. In fact, her costume started even more revealing, which then caused new regulations towards hero attire because it was deemed too inappropriate. She is very free spirited but also very caring and we can see that during Aizawa's school days— if you don't think those are her boys then we did not watch the same anime— and her encouraging behavior to get Aizawa into teaching (which led her to just straight up signing him up for teaching). Midnight being risky is just part of her.
The reason why most redesigns don't come off as Midnight is because they don't capture Midnight's intended hero persona. Midnight uses her good looks to either fool or charm villains into submission. We can, once again, see her use her good looks to her advantage in vigilantes Volume 3 in the first special chapter "Hero Conference". What Midnight does to subdued a bomb-villain is pop open her blouse and push him directly into her boobs, which forces the villain to pause and let off steam, efficiently diffusing the villain's quirk. She is not ashamed of this, because she embraces it as herself and because it simply works with her image. Redesigns focus on armor and protection due to the nature of hero work, but here's where I get an issue with that: majority of heroes are PR, they need to stand out and appeal to the mass (if you're limelight obviously) and bulky armor, bullet vests and other obvious plating just doesn't achieve that. Yes, hero work is very dangerous, but in My Hero Academia I've found myself suspending my belief for a better character design. We can also go more fantasy-esque like Aizawa's scarf or Midoriya's gloves and say the materials are fine woven and defensive on their own.
Besides armor, people tend to rid Midnight of her latex and BDSM elements due to her teaching position. However, if they're learning from heroes in a hero school, Midnight is allowed to be in her hero costume. They are high-school students learning the inside workings on what it means to be a hero, and sometimes heroes take on different hero personas. Midnight is a very good example of having a hero persona, and so is All Might and Present Mic. Those three play up a personality to separate themselves slightly to not slowly wear down on their lives. Midnight plays up her sexual nature as a hero and sometimes her sadism, but it's much more toned down and joking when she is just herself. All Might always has a smile and is confident as a hero, but Yagi is a very awkward and almost shy in his Small Might form. Present Mic is very loud and comes off as either Air-headed or overly enthusiastic, but Yamada as a person is very smart and down to earth with anger issues. Making Midnight extremely kid friendly takes away what a student could learn from her persona if they wish to be like her as a hero. Having a different uniform for just teaching is stupid.
You're supposed to look at Midnight and go "holy shit she's very attractive and/or sexy", and if that redesign doesn't give that thought then you didn't make Midnight. You're just dismissive of her character.
Speaking of character, don't you EVER say that Midnight is canonically a predator (don't get me started on people calling her pedophile, which with what they're trying to imply is not the correct usage of pedophile) because of her hero persona. Her being the announcer for the Sports Festival is planned because of her quirk. She can put anyone to sleep if they inhale her gas, and when dealing with first-years, especially 1-A and 1-B who have very destructive quirks with little control (Midoriya especially), you need a swift way to take care of a situation in case of an emergency. That's also part of why Cementoss was part of being on-field, besides fixing the stage. There is also a lot more eyes on the first-years, especially 1-A due to the USJ, so having an eye-catching announcer just makes sense. Now, where the predator comments come from is when Midnight in the English dub of the anime says "That turns me on!" when Ojiro and Shoda withdraw from the finals. Before I talk about that, I would like to note that in the manga, volume 4, Midnight does not say the same thing. She instead says "How Naive and green…I like it!" while whipping her whip for emphasis. Back to the anime English dub, people tend to get weirded out by a U.A. teacher saying that in front of students. However, I argue that she is not there as a teacher, but as an announcer and as Midnight, not Midnight-sensei. She is entirely her hero persona with responsibility of making sure the matches progress smoothly. She is performing for the crowd, not teaching her students. How many times must I repeat that part of a Limelight hero's job is to perform before it sticks.
another quick note because I cannot shut up, is that the term Twilight heroes is fanon and not canon, though I very much like the idea of twilight heroes. Midnight is canonically a Limelight heroine, she is well known, as she also promotes beauty products.
Midnight is intentionally sexy and flirty, but also very motherly and caring, and loves her job as a teacher. Midnight being sexual and desirable and her being a (good) U.A. teacher do not need to be separate just because you don't understand her.
